We have preliminary evidence from model systems that enzymatic enolizations can be accelerated by binding of the substrate in a particular (reactive) conformation. We propose to extend this work to other model compounds to determine to what extent this stereoelectronic control might contribute to enzymatic rate accelerations of enolization. Compounds will be investigated which have varying degrees of freedom of rotation to assess the effect of conformational restriction on reaction velocity. In addition we will study the effect of orbital orientation on the rates of decarboxylation of Beta-keto acids and retro-aldol condensations. Those reactions will serve as models for the enzymes acetoacetate decarboxylase and aldolase.